Session

Extreme Perl

In this talk I dissect the 999 overachieving bytes of the "SelfGOL" program: an obfuscated, self-aware, viral quine that can:

self-replicate,

rewrite other Perl programs to allow *them* to self-replicate,

detect un-rewritable Perl programs,

execute itself or other Perl programs as cellular automata of arbitrary size (to play Conway's "Game of Life")

animate any short text as a cycling marquee banner.

SelfGOL accomplishes these feats in standard Perl, without importing any modules, and without using a single
if, unless,
while, until,
for, foreach,
goto, next,
last, redo,
map, or grep
statement in its
source code.

To do all that in less than 1K of code, it relies on some extreme programming techniques, and on many of the obscure backwaters of the Perl syntax. This talk explores both.